Today most people shop for fresh vegetables more on a weekly than daily basis because of time constraints and since most households have refrigerators whose use slows the biological and chemical process of decay. Temperature control however is but one facet of maintaining vegetables fresh since one of the principal mechanisms of deterioration in taste of stored vegetables in refrigerated spaces is dehydration. Vegetables, like most plants, typically lose a great deal of moisture to the atmosphere by evaporation through the leaves or the body of its fruit. While vegetables are still attached to the plant in the ground, lost moisture is replaced by their root systems. Thus, once vegetables are harvested it is important to minimize moisture losses in addition to keeping them cool to maintain freshness.
Efforts have heretofore been made to alleviate this problem. These efforts have focused on minimizing the flow of cool air, which is relatively dry, into contact with the vegetables. Typical of such is the apparatus disclosed in U.S. Pat. No. 3,364,694 which is in the form of a vegetable container that has double walls. Refrigerated air is drawn through the space between the two walls and thus is not introduced into the container. This allows the vegetables to be chilled by thermal conduction rather than convection. Another type device, which is shown in U.S. Pat. No. 4,013,434, provides dampers to restrict the flow of dry refrigerated air into a vegetable container.
Another possible approach is taught in U.S. Pat. No. 2,560,057 wherein a self-contained refrigeration unit for the aging of beef has means for humidifying the air circulated over the meat to keep it from drying out. While this may be practical for commercial meat lockers, it is not practical for small scale consumer use since household refrigerators require dry air to prevent excessive frosting of the interior of the refrigerator and since they are designed to hold and cool many diverse types of products. This also apparently would not be feasible for temporary out-of-home consumer use as, for example, in maintaining vegetables fresh on trips, picnics and the like.
Accordingly, it is seen that a need remains for apparatus for maintaining vegetables fresh and crisp within the confines of a conventional household refrigerator or in a small cooler or the like for consumer use. It is to this end that the present invention is primarily directed.